1. Field of the Invention
The present invention relates to an image forming apparatus, an image processing device, a control device, and a connection device.
2. Description of the Related Art
Conventionally, there is a technology of providing a high-speed serial bus as an internal bus in an image processing device for transferring data inside the image processing apparatus at high speed. Generally, image data are high-volume, and therefore the technology of transferring such data at high speed is important for performing high-speed processing.
For example, Japanese Laid-Open Patent Application No. 2005-148896 (Patent Document 1) discloses an invention of further increasing the processing speed of an image equipment system that uses a PCI-Express® interface (I/F) (hereinafter, “P-E”) which is a high-speed serial I/F. Specifically, plural switches are provided under a route complex. The functions connected to the switches are appropriately divided in order to separate the data transfer operation performed via the route complex and the data transfer operation performed with a switch as the highest level.
Furthermore, for example, Japanese Laid-Open Patent Application No. 2004-106456 (Patent Document 2) discloses an invention of an image forming apparatus in which a controller and an image forming function unit in the image forming apparatus are connected by a P-E bus. Accordingly, the controller and the image forming function unit are removably attached to each other, and moreover, the overall power consumption of the apparatus can be controlled.
According to the image forming apparatus disclosed in Patent Document 2, the controller and the image forming function unit can be performed on separate substrates. This configuration facilitates increasing speed, improving performance, and increasing the number of functions, which require changes in the design of a circuit board.
The “controller” and the “image forming function unit” described in Patent Document 2 correspond to the “control device” and the “image processing device” of the present invention, respectively.    Patent Document 1: Japanese Laid-Open Patent Application No. 2005-148896    Patent Document 2: Japanese Laid-Open Patent Application No. 2004-106456
However, the invention of the image forming apparatus disclosed in Patent Document 2 does not describe how the substrate having a controller function and the substrate performing the image forming function are connected to each other. The type of image processing performed by an image forming apparatus differs according to the type of image and the purpose, such as an image read with a scanner or an image to be output with a plotter. A large scale integrated circuit (LSI) or a substrate may be provided for each type of image processing. With such a configuration where each of the different substrates is connected to the substrate having the controller function with a connection unit such as a connector, it is necessary to develop each individual substrate as well as a dedicated connector for each substrate, which leads to increased development costs.